//
//  ZXLCycleView.m
//  CycleScrollView
//
//  Created by 朱兴隆 on 16/4/19.
//  Copyright © 2016年 朱兴隆. All rights reserved.
//

#import "ZXLCycleView.h"

@interface ZXLCycleView ()<UIScrollViewDelegate>
// scrollView
@property (nonatomic, strong) UIScrollView *imgScrollView;
// pageControl
@property (nonatomic, strong) UIPageControl *imgPageControl;
// ImageViewArray
@property (nonatomic, strong) NSMutableArray *imgViewArray;
// 存放图片的数组
@property (nonatomic, strong) NSMutableArray *imgArray;
// 当前展示的图片下标
@property (nonatomic, assign) NSInteger index;
// 定时器
@property (nonatomic, strong) NSTimer *imgTimer;
// 点击回调block
@property (nonatomic, copy) void(^tapBlock)(NSInteger index);
// 时间间隔
@property (nonatomic, assign) NSTimeInterval interval;

@end

@implementation ZXLCycleView

// 初始化方法
- (instancetype)initWithFrame:(CGRect)frame interVal:(NSTimeInterval)interval {
    self = [super initWithFrame:frame];
    if (self) {
        self.imgViewArray = [NSMutableArray new];
        self.imgArray     = [NSMutableArray new];
        self.imgScrollView = [[UIScrollView alloc] initWithFrame:self.bounds];
        self.imgScrollView.contentSize = CGSizeMake(frame.size.width * 3, frame.size.height);
        [self addSubview:self.imgScrollView];
        
        for (int i = 0; i < 3; i++) {
            UIImageView *imgView = [[UIImageView alloc] initWithFrame:CGRectMake(frame.size.width * i, 0, frame.size.width, frame.size.height)];
            // 添加到父视图,数组
            [self.imgScrollView addSubview:imgView];
            [self.imgViewArray addObject:imgView];
            
        }
        
        self.imgScrollView.pagingEnabled = YES;
        self.imgScrollView.showsHorizontalScrollIndicator = NO;
        self.imgScrollView.delegate = self;
        
        self.interval = interval;
        
    }
    return self;
}
- (void)timerAction {
    [self.imgScrollView setContentOffset:CGPointMake(self.imgScrollView.frame.size.width * 2, 0) animated:YES];
    // 改变index
    self.index = (self.index + 1) % self.imgNameArray.count;

}
// 滚动动画结束
- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView {
    /**
     *  回位
     */
    [self.imgScrollView setContentOffset:CGPointMake(scrollView.frame.size.width, 0) animated:NO];
    [self layoutImages];
}

// ImgNameArray 的 setter方法
- (void)setImgNameArray:(NSMutableArray *)imgNameArray {
    if (_imgNameArray != imgNameArray) {
        _imgNameArray = imgNameArray;
        
        // 设置pageControl
        [self.imgPageControl removeFromSuperview];
        self.imgPageControl = [[UIPageControl alloc] initWithFrame:CGRectMake(0, self.frame.size.height - 40, self.frame.size.width, 40)];
        [self addSubview:self.imgPageControl];
        // 小圆点不可操作
        self.imgPageControl.enabled = NO;
        // 属性
        self.imgPageControl.currentPage = 0;
        self.imgPageControl.numberOfPages = _imgNameArray.count;
        
        for (int i = 0; i < imgNameArray.count; i++) {
            UIImage *img = [UIImage imageNamed:imgNameArray[i]];
            [self.imgArray addObject:img];
            if (i < 3) {
                [self.imgViewArray[i] setImage:img];
            }
        }
        // 设置偏移量
        [self.imgScrollView setContentOffset:CGPointMake(self.frame.size.width, 0) animated:NO];
        self.index = 0;
        [self layoutImages];
        
        // 点击手势
        UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapCycleViewAction:)];
        [(UIImageView *)self.imgViewArray[1] addGestureRecognizer:tap];
        [(UIImageView *)self.imgViewArray[1] setUserInteractionEnabled:YES];
        
        if (self.interval <= 0) {// 还未开启imgTimer,interval未定义
            self.imgTimer = [NSTimer scheduledTimerWithTimeInterval:3 target:self selector:@selector(timerAction) userInfo:nil repeats:YES];
        }else {
            self.imgTimer = [NSTimer scheduledTimerWithTimeInterval:self.interval target:self selector:@selector(timerAction) userInfo:nil repeats:YES];
        }

    }
}
- (void)tapCycleViewAction:(UITapGestureRecognizer *)tap {
    if (self.tapBlock) {// 若self.tapBlock存在
        self.tapBlock(self.index);
    }
    
}

#pragma mark - UIScrollViewDelegate
static CGFloat x = 0;
// 开始拖
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView {
    x = scrollView.contentOffset.x;
    
    [self.imgTimer setFireDate:[NSDate distantFuture]];
}
// 减速结束
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
    if (x > scrollView.contentOffset.x) {
        [self panToLeft:NO Index:self.index];// 右滑
        NSLog(@"%ld",self.index);
    }else if(x <scrollView.contentOffset.x) {
        [self panToLeft:YES Index:self.index];// 左滑
        NSLog(@"%ld",self.index);
    }
    [self.imgTimer setFireDate:[NSDate dateWithTimeIntervalSinceNow:2]];
}

#pragma mark - 向左滑动,向右滑动结束切换
- (void)panToLeft:(BOOL)left Index:(NSInteger)index {
    if (!left) {
        self.index = (index - 1 + self.imgNameArray.count) % self.imgNameArray.count;
    }else {
        self.index = (index + 1) % self.imgNameArray.count;
    }
    
    // 切换图片
    [self layoutImages];
    // 回位操作
    [self.imgScrollView setContentOffset:CGPointMake(self.frame.size.width, 0) animated:NO];
    
}
- (void)layoutImages {
    // 更新 3 张图
    for (int i = 0; i < 3; i++) {
        [self.imgViewArray[i] setImage:self.imgArray[(self.index - 1 + i + self.imgNameArray.count) % self.imgNameArray.count]];
    }
    
}
// index 的 setter方法
- (void)setIndex:(NSInteger)index {
    if (_index != index) {
        _index = index;
        self.imgPageControl.currentPage = index;
    }
}

// 添加block
- (void)addTapBlock:(void (^)(NSInteger))block {
    self.tapBlock = block;
}
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
    // Drawing code
}
*/

@end
